This application requests support to continue the ?Host-Microbe Interactions (HMI) Predoctoral Training Program? that is the centerpiece of the acclaimed Microbiology and Molecular Pathogenesis Program (M2P2) at Dartmouth. The HMI Training Program is an interdisciplinary training program that seeks to provide research and curricular-based training to a pool of talented and highly motivated students who have been recruited into our trainers? labs. Particular areas of strength include molecular genetics of bacterial, fungal, parasitic, and viral pathogenesis, and prion biology, interaction with the innate and adaptive immune systems, signaling events in host-pathogen interactions, chronic and sustained infections, therapeutic and vaccine design, and translational research. These areas are pursued using the full range of modern genetic, molecular, biochemical, immunologic, and computational techniques. The contribution of the HMI Training Program to the Dartmouth biomedical research community has been overarching and significant as is reflected in the detailed External Advisory Committee review in 2015. The HMI program consists of 22 well- funded trainers ($20.8M direct costs in 2017) who currently have 73 trainees in their labs. In 2017, we hired new faculty whose research is directly aligned with the program goals and who are included as Trainers in this application highlighting microbiology as an area of investment at Dartmouth. Most importantly, our past Trainees have been extremely successful with 96% of 32 HMI Training Program Graduates who have left Dartmouth continuing on in research careers. In total, HMI Trainees have published more than 200 papers over the twenty-year span of the program. Our program is located within outstanding state-of-the art facilities with resources housed in modern space in a pleasant working environment. Dartmouth has invested and continues to invest heavily in its biomedical sciences infrastructure as well as in faculty recruitment in this area. We request to continue supporting five trainees per year. Students to be trained in this program are generally selected from the Molecular and Cellular Biology (MCB) multidisciplinary graduate program, which is the largest graduate program at Dartmouth. Students are nurtured in this highly interactive environment in which all trainees enroll in a core course, several courses in ethics, and several advanced courses and career development workshops pertinent to their area of research training. In addition, they participate in weekly seminar series and journal clubs, and present their work at joint lab meetings and retreats. The trainees supported by the T32 are provided with a series of additional enrichment activities, particularly relating to professional development, as described in the Research Training Program Plan.